Systems and methods for dispensing product

ABSTRACT

The present invention relates to systems and methods for producing and dispensing aerated and/or blended products, such as food products.

RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.10/726,815, filed Dec. 3, 2003, which is a Division of U.S. applicationSer. No. 10/160,674 (now U.S. Pat. No. 6,698,228), filed Jul. 31, 2002.This application is also a continuation-in-part of U.S. application Ser.No. 10/359,834, filed Feb. 7, 2003. This application also claims thebenefit of U.S. Provisional Applications No. 60/336,252, filed Nov. 2,2001 (the benefit of which was claimed in U.S. Ser. No. 10/359,834), andNo. 60/644,258, filed Jan. 14, 2005. The entire teachings of each ofthese references is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

This invention relates to systems and methods for producing anddispensing aerated and/or blended products, such as food products. Whilethe invention may be used to produce a variety of products, it hasparticular application to the production and dispensing of frozenconfections such as ice cream and frozen yogurt. Consequently, we willdescribe the invention in that context. It should be understood,however, that various aspects of the invention to be described also haveapplication to the making and dispensing of various other food products.

BACKGROUND

Aerated frozen food products can be produced by mixing selected liquidingredients with a prescribed volume of air and then freezing anddispensing the resultant mixture. The desirability of the finishedproduct is often related directly to the manner in which, and to thedegree to which, the air is metered and blended with the liquidingredients of the mixture, referred to as overrun, and the manner inwhich the blended mix is frozen and then dispensed. Prior machinesinclude many examples that dispense ice cream and other semi-frozendairy products such as soft ice cream and frozen yogurt.

Conventionally, such machines are usually dedicated to dispensing one ortwo flavors of product and, in some cases, a combination of the two. Forexample, in an ice cream shop, there may be one machine with twoseparate freezing chambers for making and dispensing chocolate andvanilla ice cream, a second two-chamber machine for making anddispensing strawberry and banana ice cream, a third machine dedicated tomaking and dispensing coffee and frozen pudding flavors, and so on. Thereason for employing multiple machines is that each chamber typicallycontains a volume of ice cream greater than is required for a singleserving. In order to dispense a different flavor ice cream, that chambermust be emptied and cleaned before the new flavor can be made in thatchamber and appear at the outlet of the dispenser. Additionally, the vatof pre-flavored mix from which the frozen product is made must also beclean enough to at least meet applicable health regulations. While highvolume ice cream shops and confectionery stores may be able toaccommodate several dispensing machines dispensing many differentproducts and flavors, smaller sales outlets can usually only accommodateone or two such machines and are thus restricted in the number offlavors that they can offer to customers.

Further, because the product is typically formed in a quantity that isgreater than that to be dispensed at any one serving, the excess productremains in the chamber after formation and until additional servingsdraw it down. The excess is thus subjected to further freezing, whichpromotes crystallization. Because of the relatively large quantity ofthe premixed flavors, and the continuous freezing of several quarts ofthe product, the freshness and palatability of the product may beadversely affected in outlets with relatively slow sales of the product.

Another disadvantage of many prior dispensers is that they have multipleinterior surfaces and moving parts, as the cleaning and maintenance ofthose surfaces and parts at the end of each day or at intervalsprescribed by local Health Department regulations is difficult andtime-consuming. Each dispenser must be purged of any remaining product,and it's chamber walls, pumps and other internal parts cleanedthoroughly to prevent growth of bacteria that could otherwisecontaminate the product being delivered by the dispenser. Not only isthe cleaning operation expensive in terms of down time, it is alsocostly in terms of product waste. Furthermore, it can be an unpleasanttask that is difficult to get employees to do properly.

While machines that dispense ice cream exist, until now no way has beenfound to provide a single machine capable of efficiently andeconomically making and dispensing different frozen food confections ina wide variety of flavors and in different formats, e.g., in a cup orcone.

SUMMARY

Described herein are systems and methods for producing and dispensingaerated and/or blended products, such as food products. One embodimentof an apparatus for producing a food product includes a frame to whichis coupled a base-mix module, a flavor module, a flavor-selectionassembly, a conduit configuration, and a food-preparation assembly.

The base-mix module supplies a base mix, while the flavor moduleprovides flavoring. Both the base-mix module and the flavor module caninclude a plurality of holding bays, each bay being filled with adifferent base mix or flavor so as to allow selection from amongst thedifferent base mixes and flavors. The base mixes and flavors can becontained in sealed packets that are loaded into the respective holdingbays. A plurality of positive-displacement pumps can be coupled with theholding bays for the flavors so as to be able to receive the flavors asthey are dispensed from the bays. The flavoring flows through aflavor-selection assembly and mixed with the base mix, which is aerated.Mix-ins, such as chips or nuts, can also be added from a mix-in moduleand mixed with the base mix.

After mixing and aeration, the flavored base mix is sprayed into afood-preparation assembly, where the mix is spread across a rotatingfreeze surface of a food-surface assembly. Refrigerant can be passedthrough the food-surface assembly to freeze the mix to form, e.g., icecream.

The operation of the apparatus is governed by a main controller and aplurality of sub-controllers. Separate sub-controllers can be providedfor the base-mix module, the flavor module, the flavor-selectionassembly, and the food-preparation assembly, as well as forsub-components of these modules/assemblies.

BRIEF DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

FIG. 1 is a front view of a food service machine according to oneembodiment of the invention;

FIG. 2 is a perspective view of one embodiment of a base-mix module foruse in the food service machine of FIG. 1;

FIG. 3 is an exploded view version of FIG. 2;

FIG. 4 is a perspective views of the base refrigeration subsystem of thebase-mix module of FIG. 2;

FIG. 5 is a schematic view of the control box for the base-mix module ofFIGS. 2-4;

FIG. 6 is a perspective view of one embodiment of a flavor module foruse in the food service machine of FIG. 1;

FIG. 7 is a front view and FIG. 8 is an exploded schematic perspectiveview of FIG. 6;

FIG. 9 is a back view of the flavor module of FIG. 6;

FIG. 10 is perspective view of the back of the flavor module of FIG. 6;

FIG. 11 is an exploded perspective view of a positive-displacement pump;

FIG. 12 is another exploded schematic perspective view of portions ofFIG. 6 including a linear drive;

FIG. 13 is an exploded schematic perspective view of one embodiment of amix-ins module for use in the food service machine of FIG. 1;

FIG. 14 a mix-in assembly used in the mix-ins module of FIG. 13;

FIG. 15 is an exploded schematic perspective view of one embodiment of aprimary refrigeration system and food preparation apparatus for use inthe food service machine of FIG. 1;

FIG. 16 is an assembled schematic perspective view of the primaryrefrigeration system and food preparation apparatus of FIG. 15;

FIG. 17 is an exploded perspective view of a freeze-surface assembly ofthe food preparation apparatus of FIG. 15;

FIG. 18 is an exploded perspective view of a rotating freeze-surfaceassembly (i.e., the food preparation apparatus) of FIG. 15;

FIG. 19 is an assembled perspective view of the food preparationapparatus of FIG. 18;

FIG. 20 is an exploded perspective view of a lower seal housing assemblyof the food preparation apparatus of FIG. 18;

FIG. 21 is an exploded perspective view of an upper seal housingassembly of the food preparation apparatus of FIG. 18;

FIG. 22 is a cross-sectional view of a portion of the food preparationapparatus of FIG. 15;

FIG. 23 is a top perspective view of one embodiment of a food coverassembly for use in the food service machine of FIG. 1;

FIG. 24 is a bottom perspective view of the food cover assembly of FIG.23;

FIG. 25 is an exploded perspective view of the food cover assembly ofFIG. 23;

FIG. 26 is a top perspective view of the food cover assembly of FIG. 23;

FIG. 27 is a sectional view of the pinion interface of the food coverassembly of FIG. 26;

FIG. 28 is a sectional view of a level interface (including a squeegee)of the food cover assembly of FIG. 26;

FIG. 29 is a sectional view of the forming/dispensing cylinder of thefood cover assembly of FIG. 26;

FIG. 30 is a top perspective exploded view of the food zone cover ofFIG. 23;

FIG. 31 is an illustration of one embodiment of the squeegee of FIG. 23;

FIG. 32 is a schematic view of one embodiment of a flavor wheel assemblyfor use in the food service machine of FIG. 1;

FIG. 33 is a cross-sectional view of the flavor wheel assembly of FIG.32;

FIG. 34 is an exploded top perspective view of the flavor wheel assemblyof FIG. 32;

FIG. 35 is a top perspective view of the flavor assembly wheel of FIG.32;

FIG. 36 is an exploded perspective view of one embodiment of a baseaeration conduit assembly (with a connection for connecting to theflavor module) for use in the food service machine of FIG. 1;

FIG. 37 is a front view of one embodiment of a process plate assembly,i.e., a process box, for use in the food service machine of FIG. 1;

FIG. 38 is a perspective view of the process box of FIG. 37;

FIG. 39 is a top view of the process box of FIG. 37;

FIG. 40 is a right side view of the process box of FIG. 37;

FIG. 41 is a top perspective view of one embodiment of a pneumaticmodule for use in the food service machine of FIG. 1;

FIG. 42 is an exploded view and FIG. 43 is a perspective view of thepacking plate piston assembly of the process box of FIG. 37;

FIG. 44 is an exploded view and FIG. 45 are perspective views of thepacking piston assembly of the process box of FIG. 37;

FIG. 46 is an exploded view and FIG. 47 is a perspective view of thepinion drive piston assembly of the process box of FIG. 37;

FIG. 48 is a schematic illustration of one embodiment of the primaryrefrigeration system of FIG. 15 and highlights a cooling loop;

FIG. 49 is the schematic illustration of FIG. 48 highlighting thecooling loop in combination with a temperature-control loop;

FIG. 50 is the schematic illustration of FIG. 48 highlighting a defrostloop;

FIG. 51 is a schematic illustration of the hot-gas valve control usedwith the system of FIG. 48;

FIG. 52 is a schematic illustration of the liquid stepper control usedwith the system of FIG. 48;

FIG. 53 is one embodiment of a timing diagram for operation of theprimary refrigeration system during a serving sequence;

FIG. 54 is the schematic illustration of FIG. 48 with each of the partscalled out for use with a parts list; and

FIG. 55 is one embodiment of a serving sequence timing diagram foroperation of the food service machine of FIG. 1.

DETAILED DESCRIPTION

The present invention relates to systems and methods for producingaerated and/or blended food products. While the invention may be used toproduce a variety of products, it has particular application to theproduction of frozen confections such as ice cream and frozen yogurt.Consequently, we will describe the invention in that context. It shouldbe understood, however, that various aspects of the invention to bedescribed also have application to the making and dispensing of variousother food products.

Referring to FIG. 1 of the drawings, one embodiment of an apparatus forproducing food according to the invention is a stand-alone unit 200housed in a cabinet 19 having a top wall 19 a, opposite sidewalls 19 band 19 c, a bottom wall 19 d, and a middle separation wall 19 e as wellas a rear wall (not shown). In one embodiment these walls are merelycovers. The front of the cabinet is open for the most part except for alow front wall 10 containing louvers to provide inlet air to a primaryrefrigeration unit, a base refrigeration unit and to pneumatics. Thefront opening into the cabinet may be closed by hinged doors 21 a, 21 b,21 c which may be swung between an open position wherein the doors allowaccess to the interior of the cabinet and a closed position wherein thedoors cover the openings into the cabinet. Suitable means are providedfor latching or locking each door in a closed position.

As shown in FIG. 1, a relatively large opening or portal 17 is providedin door 21 c so that when the door is closed, the portal 17 providesaccess to a dispensing station 20 within the cabinet at which a customermay pick up a food product dispensed by the apparatus. Preferably, theportal is provided with a door so that the portal is normally closedblocking access to station 20. A customer may select the particularproduct to be dispensed by depressing the appropriate keys of a controlpanel mounted in door 21 c after viewing product availability. In theevent the apparatus is being used as an automatic vending machine, thecontrol panel may include the usual mechanisms for accepting coins,debit cards and currency and possibly delivering change in return. Foradvertising purposes, an illuminated display may be built into the frontof a door, e.g., door 21 c.

Having described the housing and the doors for the housing, thisdescription now turns to an overview of the apparatus 200 of FIG. 1. Oneembodiment of an apparatus for producing a food product includes: ahousing/frame 19; a base-mix module 12 coupled to the frame andoperative to provide refrigerated base mix and; a flavor module 14coupled to the frame and operative to provide flavoring; aflavor-selection assembly 208 (shown in FIGS. 32-34 and 37) coupled tothe frame and having an outlet 118 and a plurality of, e.g., twelve,flavoring inlets 116 a, 116 b, each inlet operative to receive aflavoring. The flavor-selection assembly 208 allows passage of aflavoring from a selected inlet to the outlet. The apparatus furtherincludes a conduit assembly 120 (shown in FIG. 36) having a proximal end120 a including a first opening 121 coupled to the base-mix module and asecond opening 123 for receiving air. The conduit assembly 120 has adistal end 120 b coupled to the outlet of the flavor-selection assembly208. The conduit assembly 120 combines base mix, air and flavoring toproduce a flavored, aerated mix.

The apparatus for producing a food product can further include a mix-insmodule 16 (shown in FIG. 1). The apparatus includes a food-preparationassembly 22 (shown in FIG. 1) coupled to the frame below a process box24. In one embodiment, the food-preparation assembly 22 includes afood-zone cover apparatus 93 (see FIG. 23) adapted to receive theflavored, aerated mix from the distal end of the conduit assembly 120and mix-ins from the mix-ins module 16. The food-preparation assembly 22then prepares food from the flavored aerated mix and mix-ins.

In one embodiment, the invention uses distributed computing tofacilitate the testing, repair and/or replacement of the individualmodules/components described above. More specifically, in one embodimentvarious modules/components have dedicated sub-controllers. Thus, in oneembodiment, the base-mix module 12 has a dedicated base-mix-modulesub-controller adapted to operate the base-mix module, the flavor module14 has a dedicated flavor-module sub-controller adapted to operate theflavor module, the flavor-selection assembly has a flavor-selectionassembly sub-controller adapted to operate the flavor-selectionassembly, and the food-preparation assembly 22 has a dedicatedfood-preparation assembly sub-controller adapted to operate thefood-preparation assembly 22. In one embodiment, the sub-controllers canbe conventional cards implemented in a combination of hardware andfirmware and designed to comply with the controller area network open(CANopen) specification, a standardized embedded network with flexibleconfiguration capabilities. The CANopen specification is available fromCAN in Automation (CiA) of Erlangen, Germany, an international users'and manufacturers' organization that develops and supports CAN-basedhigher-layer protocols.

The apparatus further includes a control and power distribution box. Thebox includes an apparatus or main controller in communication with thebase-mix-module sub-controller, the flavor-module sub-controller, theflavor-selection assembly sub-controller, and the food-preparationassembly sub-controller to provide instructions to the sub-controllersso as to operate the apparatus. Similarly, the mix-ins module 16 caninclude a dedicated mix-ins-module sub-controller in communication withthe apparatus/main controller adapted to operate the mix-ins module 16.In one embodiment, the main controller communicates with thesub-controllers over a bus using CANOpen, a controller areanetwork-based higher layer protocol. CANOpen is designed formotion-oriented machine control networks, such as handling systems.

The main controller includes a digital I/O board with an associatedCANOpen gateway, a CANOpen adaptor in communication with the CANOpengateway, a motherboard in communication with the digital I/O board, themotherboard having an associated hard drive. The main controller furtherincludes an Ethernet connection and two USB connectors in communicationwith the motherboard for providing external access to the motherboard.

The Base-Mix Module

With reference to FIGS. 2 and 3, one embodiment of a base-mix moduleincludes: two base-mix holding bays 30 a, 30 b; two base mix conduits 32each having a proximal end and a distal end (the proximal end adaptedfor coupling to a bag held in one of the base-mix holding bays); twopumps 26 a, 26 b, e.g., peristolic pumps, each pump coupled to a basemix conduit, the base mix conduits couple to a conduit assembly (shownin FIG. 36) forming a conduit assembly; a source of compressed air 244(shown in FIG. 42) couples to the base mix conduit, the source ofcompressed air controlled in part by an air-control valve 202 a (shownin FIG. 4). The air-control valve is operative to control the amount ofair provided to the conduit assembly; and a base-mix-modulesub-controller coupled to the pumps and operative to control the pumpsand the air-control valve so that, when base mix is loaded into thebase-mix holding bay, the base-mix-module sub-controller controls theamount of base mix and air injected into the conduit assembly.

More specifically and with reference to the embodiment illustrated inFIGS. 4 and 5, the base-mix-module sub-controller 159 includes four (4)cards, i.e., a digital input/output (I/O) board 153 with a CANOpengateway 153, an analog I/O board 154, a first motor control board 156for operating the first pump 26 a, and a second motor control board 158for operating the second pump 26 b (the pumps are shown in FIG. 2). Inone embodiment, the analog board and the motor control boards aredaisy-chained to the digital I/O board. The purpose of the analog cardis to receive thermocouple information from appropriately placedthermocouple(s), the thermocouple information allows the system tocontrol the base refrigeration system to hold the base mix temperaturewithin a specified temperature range, e.g., at or below about 41 degreesFahrenheit (5° C.).

The Flavor Module

With reference to FIGS. 6 to 12, one embodiment of a flavor module 14includes a plurality of flavor-packet holding bays 37 defined bybrackets 44 and shelf (shelves) 45. Each holding bay 37 holds a flavorpacket 36. The illustrated flavor module 14 includes a plurality of,e.g., 12, positive-displacement pumps 50 attached to pump frame 61(shown in FIGS. 7-9) to form two pump banks 50 a, 50 b. Each pump 50couples to a holding bay 37 via a fitting 42 and tubing 43. An operatorcan attach the fitting 42 to a container (e.g., a bag) of flavoring andinsert the flavor container into a holding bay 37. Flavor flows from aflavor container through the fitting 42 and tubing 43 into adisplacement pump 50. Thus, displacement pumps 50 receive flavoring fromflavor containers/packets held in the holding bays 37.

With reference to the embodiment of FIG. 11, the pump 50 includes apiston 56 seated on top of the pump body 59 and supported by a pistonspring 54. The pump 50 further includes a check valve system. Each checkvalve includes a barb fitting 53, a spring 55, and a ball 57. An inletcheck valve 170 is on the front side 59, i.e., the side having twoorifices; and an outlet check valve 171 is on the bottom of the pump 50.

The illustrated flavor module 14 includes a plurality of, e.g., twelve,electrical solenoids 48 coupled to slidable support plates 39 a, 39 b toform two solenoid banks 39 c, 39 d. Support plate 39 a slidably coupleswith two support shafts (one of which is designated 59 a and the otherof which is not shown). Similarly, support plate 39 b slidably couplesto two support shafts 59 b, 59 c. Thus, the support plates can slide upand down on their support shafts.

The flavor module 14 includes a linear-drive motor 46 coupled to theslidable, support plates 39 a, 39 b to drive the support plates alongthe support shafts so as to bring the solenoid banks 36 c, 39 d in (orout of) contact with the pump banks 50 a, 50 b. When the solenoid banks39 c, 39 d come in contact with the pump banks 50 a, 50 b, each solenoid48 engages with an associated displacement pump 50 to cause at least onedisplacement pump 50 to dispense flavoring. The flavor module 14 furtherincludes a flavor-module sub-controller in communication with each ofthe solenoids 48 and with the linear-drive motor 46. The sub-controllercontrols each of the solenoids 48 and the linear-drive motor 46 so as toselect and energize at least one solenoid 48 and to operate thelinear-drive motor 46 to drive a slidable support plates 39 a/39 b,moving the associated solenoid bank 39 c/39 d relative to thedisplacement pumps 50 such that an energized solenoid 48 causes anassociated displacement pump 50 to dispense flavoring. Morespecifically, in the illustrated embodiment (see FIGS. 9, 10 and 12),the flavor-module sub-controller includes a linear-drive board 13 foroperating the linear drive 46, a first solenoid-bank board 11 foroperating the first solenoid bank 39 c, and a second solenoid bank board15 for operating the second solenoid bank 39 d. Thus, in one embodimentthe system uses a single precisely controlled conventional linearactuator to drive and pump a number of, e.g., twelve, different flavors.

With reference to FIGS. 9 and 12, linear-drive motor 46 includes a driveshaft 41 connected via a coupling assembly (including hubs 51 a, 51 cand disc 51 b) to a male/female screw (not shown). The male part of thescrew is on a coupler shaft 47 and the female part is on the housing.The male/female screw assembly provides precise position control. Theprecision control assembly is a conventional assembly. As noted above,support plates 39 a, 39 b support solenoids 48 to form solenoid banks 39c, 39 d. The coupler shaft 47 (see FIG. 10) coming down from the linearmotor 46 directly attaches to the support plates 39 a, 39 b. As notedabove, the top support plate 39 a has two support shafts and the bottomsupport plate 39 b has two support shafts. The support shafts connect tothe support plates with precise bearings to keep the support platesparallel and square with each other so that as the linear-drive motormoves the support plates, it moves both plates simultaneously and in acontrolled manner. In other words, in one embodiment the lead screw andmotor assembly move the top plate 39 a and the bottom plate 39 b as asingle unit.

In operation, when a user selects a flavor, the flavor module controlscheme determines which pump e.g., of twelve available pumps—correspondswith a selected flavor/pump. The flavor module control scheme run by themain controller energizes the solenoid associated with the selectedflavor. Energizing the appropriate solenoid 48 locks the solenoid rod 63extending from the bottom of the solenoid 48. All other solenoids areleft in an un-energized state, which allows their rods to move up anddown freely. Then the linear-drive motor (actuator) 46 drives thesolenoid banks 39 c, 39 d down into contact with the pump banks 50 a, 50b. A flavor-module sub-controller, e.g., an appropriately programmed PC,provides instructions to the linear-drive motor (actuator) 46 on howfast to accelerate, how fast to move through the full acceleration andhow long to operate which determines the displacement (length of stroke)of the single linear-displacement motor 46.

The solenoid rod 63 for the energized solenoid 48 is stationary and allthe other solenoid rods are free to move longitudinally, e.g., up anddown. Thus only the solenoid rod 63 for the energized solenoid 48 pushesdown on an associated pump piston 56, which is resisted by spring 54.The other 11 solenoids are at rest and their solenoid rods are thus freeto move inside their associated solenoid bodies. In other words, whenthe metal rod inside the coil of the resting, i.e., non-energized,solenoid 48 encounters a pump piston 56 it merely slides in the solenoidbody without displacing the piston 56.

The displacement pumps 50 are already full of flavor because of aprevious stroke. The drive shaft 41 of the linear-drive motor 46downwardly displaces the support plates 39 a, 39 b and associatedsolenoid banks 39 c, 39 d. As a result, the rod 63 of aselected/energized solenoid 48 pushes down on its associated pump piston56 and, consequently, the associated pump 50 ejects flavor via itsoutlet to a flavor-selection assembly 208, e.g., a flavor wheel (seeFIGS. 32-35). Pushing against piston 56 displaces the lower check valve171, and drives material out into a flavor-selection assembly 208. Then,as the drive shaft 41 of the linear-drive motor (actuator) 46 moves backin a controlled manner (not an instantaneous release) to its homeposition, or base position, the check valve 171 on the bottom seatsitself, and the inlet check valve 170 on the front of the pump 50unseats itself creating a suction on an associated flavor storage bagand the pump 50 refills with flavoring. Thus, a singular linear-drivemotor 46 pumps at least one of a plurality of, e.g., twelve, differentflavors.

The Mix-Ins Module

With reference to FIGS. 13 and 14, one embodiment of a mix-ins module 16includes a plurality of mix-in assemblies 65. Each assembly 65 includesan auger block 60 forming a storage container orifice 69 (adapted toreceive a mix-in storage container, such as bottle 58); an auger passage71 coterminous with the container orifice 69 so as to allow flow fromthe container 58 through the container orifice 69 and then through theauger passage 71; and a dispensing orifice 73 coterminous with the augerpassage 71 so as to allow flow through the auger passage 71 and thenthrough the dispensing orifice 73. Each assembly 65 further includes anauger 68 adapted to sit in the auger passage 71 of the auger block 60,the auger 68 having an engagable end 67. The mix-ins module 16 includesa plurality of drive assemblies 66 coupled to the engagable end of theaugers 68 via auger drive 62 and operative to drive the augers 68.

The mix-ins module 16 includes a trough assembly 64 having a collectionslot 64 a and a dispensing opening 64 b. The collection slot 64 a isaligned with the dispensing orifices of the plurality of mix-inassemblies 65 to form a continuous passage therethrough. In oneembodiment, the trough assembly 64 includes a trough cover 64 c. Thetrough assembly 64 receives mix-ins from the mix-in assemblies 65 anddispenses the mix-ins via dispensing opening 64 b. The mix-ins module 16further includes a mix-ins-module sub-controller in communication witheach of the mix-in assemblies 65. The sub-controller controls the driveassemblies so that, when mix-ins containers are loaded into the mix-insmodule 16, the sub-controller drives the engagable ends 67 to turn theaugers to dispense mix-ins. In the illustrated embodiment, themix-ins-module sub-controller includes a motor control board 150 foroperating a motor (not shown) that drives the drive assemblies. Themix-ins sub-controller further includes a CANOpen gateway board 151 incommunication with the motor control board 150 and with the maincontroller via a bus.

Food Preparation Apparatus/Assembly

With reference to FIGS. 15-22, one embodiment of an apparatus forpreparing food includes a food-surface assembly 70, e.g., a freezesurface assembly, having a central axis and a periphery. The assembly,shown upside down in FIG. 17, includes an upper freeze plate 86 having afirst face (i.e., a rotary freeze surface) 70 a and a second face 172(see FIGS. 15-17). In one embodiment, the base material is aluminum,which facilitates heat transfer and is damage resistant and low weightrelative to other practical materials. The first face, which is a highlypolished nickel-plated surface, forms a non-stick rotary freezingsurface that readily releases food products at low temperatures. Thenickel plating provides strength and is conventional for foodpreparation applications. The nickel plating facilitates the system'sability to scrape ice cream off the surface without the ice creamsticking to the surface.

The second face 172 has a refrigerant channel 85 operative to passrefrigerant. The assembly includes a gasket 84 adapted to couple to theupper freeze plate 86 and operative to reduce cross flow of refrigerant.In one embodiment, the gasket 84 is made of a conventional type ofneoprene specifically designed for refrigerant applications. Theassembly 70 includes a lower freeze plate 82 coupled to the upper freezeplate 86 so as to sandwich the gasket 84 between the lower and upperfreeze plates 82, 86. The lower freeze plate 82 has a first face (notshown) and a second face 173. The first face seals the refrigerantchannel 85, leaving the refrigerant channel 85 with an entrance orifice82 a and an exit orifice 82 b. A number of screws attach the bottomfreeze plate 82 to the upper freeze plate 86. Using a pattern offastening that places screws adjacent to both sides of the refrigerantchannel 85 helps to maintain the channel 85 and facilitates the functionof gasket 84.

Thus, the food-surface assembly 70 creates refrigerant passages for therefrigerant to enter the food-surface assembly 70, to circulate aroundthe entire channel 85 and then exit. Liquid refrigerant comes in toentrance orifice 82 a, moves through the entire channel and then exitsvia exit orifice 82 b. In an alternative embodiment, copper tubes arepressed into features machined into the upper freeze plate 86. However,elimination of the copper tubing improves the heat transfercharacteristic. The assembly 70 further includes an insulation plate 87coupled to the lower freeze plate 82 and operative to provide insulationto the food-surface assembly 70. In one embodiment, the insulation plate87 is foam insulation that is glued to lower freeze plate 82. The lowerfreeze plate 82 includes a number of orifices 82 c that are not used forfastening, but that are used for pressure relief so that if the systemdoes build up excessive pressure the pressure will be relieved via theorifices in the lower freeze plate 82.

A thermocouple assembly 88 passes through lower freeze plate 82, and isepoxied with silver filled epoxy to upper freeze plate 86 to withinbetween 0.005 and 0.01 of an inch from the top of the rotary freezesurface 70 a. The thermocouple 88 is part of a system that measures thesurface temperature and acts as one of a plurality of feedback loops fortemperature control.

The apparatus for preparing food includes a drive shaft 265 (shown inFIG. 22) coupled to the food-surface assembly 70. With reference to FIG.15, the apparatus further includes a drive motor 72 coupled to the driveshaft 265 and operative to rotate the drive shaft 265 causing rotationof the rotary surface about the central axis. More specifically, thedrive motor 72 drives a pulley 74 that, in turn, drives a timing belt 76to drive a pulley 78 attached to the drive shaft 265 (shown in FIG. 22)to rotate the food-surface assembly 70. The apparatus further includes acontrol box 80 (shown in FIG. 15). The control box 80 contains asub-controller coupled to the drive motor 72 and operative to controlthe drive motor 72 to control the rate of rotation of thefood-preparation assembly 22. The sub-controller can be a conventionalmotor control card that adheres to the CANOpen specification, such asmotor control cards available from Elmo Motion Control, Inc. ofWestford, Mass.

Thermocouple Slip Ring

With reference to FIGS. 15-19, a conventional slip ring assembly(typically used for transmitting power) is used for transmittingtemperature measurements from the thermocouple assembly 88 to thesub-controller 80. Thus, the system transmits low voltages through theslip ring assembly, which includes a slip ring 15 a, a first slip ringmount 77 and a second slip ring mount 83. A plastic collar 81 helps tokeep the slip ring assembly from freezing. If the slip ring assemblygets too cold, moisture from the air can condense on the slip ringassembly either causing the assembly to freeze up or resulting in erranttemperature readings. Thus the plastic collar acts as an insulatorbetween the slip ring 15 a and the shaft 265 eliminating directmetal-to-metal contact.

The system, also uses a conventional seal 20 as a moisture barrier. Theseal 20 keeps moisture out of the system and away from the shaft 265 andany housings to prevent moisture from being pulled into the shaft 265and housings. Moisture in the system, e.g., on the shaft 265, can freezeand ultimately lock the shaft 265, i.e., prevent rotation of the shaft265.

Rotary Coupling

With reference to FIGS. 17-22, food-surface assembly 70 contains a fluidpath 85. The fluid path 85 has ends that are connected by a rotarycoupling 261 to fluid lines leading to and from a primary refrigerationsystem. The rotary coupling includes an upper seal housing 204 and alower seal housing 205. The housings are modular housings that hold bothsupport bearings and rotating refrigerant shaft seals. The sealsthemselves are conventional seals.

The modular design facilitates testing prior to assembly. Thus, systemassemblers do not have to wait until the food-surface assembly 70 isinstalled inside the unit (shown as element 200 in FIG. 1) to test forleaks. Having to wait for full assembly to test for leaks means thatwhen a leak occurs the assemblers have to disassemble the unit, atime-consuming task.

More specifically, with reference to FIG. 22, moving from top to bottomof the figure, is shown a drive shaft 265 and a driven gear 78 and,further down, the upper housing module 204 including a large bearing283, a seal retainer plate 278 with a set of screws, a channel 275,another retainer plate 283 and another bearing 283. This configurationis repeated in the lower seal housing 205. This configuration creates arefrigerant passage and seals the passage so that the refrigerant doesnot escape.

Thus, the upper seal housing 204 has an inlet 267 for receivingrefrigerant. The refrigerant travels along the center of the shaft 265via channel 269 where it is coupled to the food-surface assembly 70. Therefrigerant passes through the serpentine channel 85 milled in the upperfreeze plate 86. The refrigerant then exits the food-surface assembly 70and travels along the shaft 265 via channel 273 and exits via outlet 271in the lower seal housing 205.

A mount 281 functions to mount the entire assembly 70 to the primaryhousing 19. A second plate 279 with an associated nut and bolt assemblyallows one to adjust for pitch and yaw to help maintain the physicalrelationship between the freeze plates and a process box/module 24 thatresides above the food-surface assembly 70.

With reference to FIGS. 17, 18 and 22, the food-surface assembly 70further includes a lower shaft 203 and an upper shaft 210. O-rings 202 aprovide a face seal between the upper shaft 210 and the inlet 82 a andoutlet 82 b. Similarly O-rings 202 b provide a face seal between thelower shaft 203 and the upper shaft 210.

Food Zone Cover

With reference to FIGS. 15, and 23-31, one embodiment of a food-zonecover apparatus 93 includes a cover 90 operative to substantiallyenclose at least a portion of a substantially horizontal, flat rotarysurface 73 a (shown in FIG. 16) to create a food zone. In theillustrated embodiment, the shape of the cover 90 mimics at least aportion of the rotary surface; e.g., FIG. 26 shows the shape of theperiphery of the cover 90 to include a substantially circular arc 90 a,the ends of which are connected by a substantially straight edge 90 b.The food-zone cover apparatus 93 includes a final mixing conduitinterface 92 coupled to the cover 90 and operative to receive liquid viaa final mixing conduit 92 a (shown in FIG. 24), the final mixing conduit92 a is operative to deposit a selected amount of liquid product mix onthe rotary surface 73 a while the rotary surface 73 a is rotating sothat the liquid product mix spreads out on the rotary surface 73 a andsets to form a thin, at least partially solidified, product body. Morespecifically, a conduit assembly couples to inlet 91 to provide aerated(typically flavored) liquid to the rotary freeze surface 73 a below thecover 90.

With reference to FIG. 24, the food-zone cover apparatus 93 includes ascraper 96 coupled to the cover 90 and supported above the rotarysurface. The scraper 96 has a working edge 96 a engaging the rotarysurface 73 a (see FIGS. 15 and 16) while the rotary surface 73 a isrotating to scrap the at least partially solidified product body into aridge row on the rotary surface 73 a.

The apparatus includes a level 94, e.g., a squeegee, coupled to thecover 90 and spaced above the rotary surface 73 a to establish a gap.More specifically, the level 94 has a working edge 94 a spaced above therotary surface 73 a to establish a gap between the working edge 94 a andthe rotary surface 73 a. With reference to FIG. 31, one embodiment ofthe squeegee includes feet 162 a, 162 b that maintain a specified gapbetween the working edge 94 a and the rotary surface 73 a. The level 94resides in proximity to the mixing conduit outlet 92 a such that whenthe rotary surface 73 a rotates in its intended direction the level 94contacts the food product, e.g., aerated, flavored liquid, before thescraper 96 contacts it so as to level the food product to a specifiedheight on the rotary surface 73 a while the rotary surface is rotatingprior to the formation of the at least partially solidified product. Inone embodiment, the gap/spacing between the working edge of the level94, e.g., squeegee, and the rotary surface 73 a is between about 0.005and 0.030 inches (i.e., between about 0.13 mm and 0.76) mm. In analternative embodiment, the gap/spacing is between about 0.015 and 0.020inches (i.e., between about 0.38 and 0.51 mm).

With reference to FIG. 25, the food-zone cover apparatus 93 includes arack and pinion structure 110, 111 coup led to the cover 90. The rackand pinion structure has a rack 110 and pinion 111. The food-zone coverapparatus 93 includes a plow 100 coupled to the rack 110 and operativeto scrape the ridge row from the rotary surface 73 a as food product.The food-zone cover apparatus 93 includes a forming cylinder 98 coupledto the cover 90 and operative to receive the food product from the plow100.

With reference to FIG. 29, the apparatus includes a diaphragm 160slidably coupled to the inside of the forming cylinder 98 so as to allowthe diaphragm 160 to move longitudinally, i.e., up and down, within thecylinder 98. Downward movement of the diaphragm 160 after insertion offood product in the forming/dispensing cylinder 98 forms the foodproduct into a scoop. In the illustrated embodiment, the bottom portionof the diaphragm 160, i.e., the portion of the diaphragm 160 that comesin contact with the food product, is semi-spherical in shape. However,the diaphragm 160 could take other shapes as is obvious to those ofordinary skill in the art. In the illustrated embodiment, the top of thediaphragm 160 has a mushroom-shaped structure 97 a with a donut-shapedcutout 97 b below the cap of the mushroom-shaped structure 97 a. Thedonut-shaped cutout 97 b receives a diaphragm piston to allow movementof the diaphragm 160 from a first retracted position to a second,extended position.

The apparatus includes a packing/cleaning plate 113 rotatably coupled tothe cover 90 via shaft 114. With reference to FIG. 29, the packing plate113 is positioned below the forming cylinder 98 to provide afood-product packing surface. In operation, a driven, rotating piston102 a rotates the packing plate 113 to clear the opening 98 a of theforming cylinder 98. Clearing the opening 98 a allows the formed/packedice cream serving to be pushed out of the forming cylinder 98 into aserving cup by longitudinal, i.e., downward, movement of the diaphragm160 to its extended position.

With reference to FIGS. 23, 26, 30, 37, and 40, one embodiment of thefood-zone cover apparatus 93 interfaces with a process box 24 thatincludes a set of pistons 97 a, 99 a, 101 a, 102 a, 103 a, 105 a, and107 a, e.g., pneumatically driven pistons. In the illustratedembodiment, the process box 24 is located above the food-surfaceassembly 70. More specifically, in operation, an operator places thefood-zone cover apparatus 93 over the rotary surface 73 a and the systemlowers pistons 97 a, 99 a, 101 a, 102 a, 103 a, 105 a, and 107 a fromthe process box 24 to hold the food-zone cover apparatus 93/cover 90 inplace and to operate the elements of the food-zone cover apparatus 93.Thus, in one embodiment, depending on local health departmentregulations periodic (e.g., daily) cleaning under normal circumstancescan be limited to a region confined by the food-zone cover 90. Whencleaning is required, the process box 24 raises its pistons 97 a, 99 a,101 a, 102 a, 103 a, 5 a, and 107 a; and an operator can remove thefood-zone cover 90 to facilitate cleaning of the cover 90 and the rotaryfreeze surface 70 a.

Thus, in one embodiment, the food-zone cover apparatus 93 includes alevel pneumatic piston interface assembly 106 coupled to the level 94and operative to interface with at least one pneumatic piston 105 a toallow control of the level 94. In the illustrated embodiment, as shownin FIGS. 26, 28 and 37, the interface assembly 106 includes downforceinterface 105 for interfacing with level downforce piston 105 a andcleaning interface 103 for interfacing with cleaning piston 103 a. Thelevel downforce piston 105 a presses on the interface 105 including alevel downforce shaft to cause the level 94 to engage with the rotaryfreeze surface 70 a. The cleaning piston 103 a engages the level 94 topress the level 94 against the rotary freeze surface 70 a for thepurpose of cleaning the level 94 to reduce carry over from one servingto another. Carry over occurs when one flavor of food product, e.g., icecream, used in a first serving contaminates a subsequently createdserving. The feet 162 a, 162 b (shown in FIG. 31) are flexible suchthat, with sufficient force, the feet 162 a, 162 b bend back and thelevel 94 presses against the rotary freeze surface 70 a for cleaning.

The food-zone cover apparatus 93 includes a pinion pneumatic pistoninterface 107 coupled to the cover 90 and to the pinion 110 a andoperative to interface with a pneumatic piston 107 a. An electric motor115 rotates the pinion piston 107 a to cause rotation of the pinion 110a and consequently movement of plow 100 attached to rack 111.

As noted above, the food-zone cover apparatus 93 includes a diaphragmpneumatic piston interface 97 coupled to the diaphragm 160 and operativeto interface with a pneumatic piston 97 a to allow control of thediaphragm 160 to form the food product. The food-zone cover apparatus 93includes a packing plate pneumatic piston interface 102 coupled to thepacking plate shaft 114 and operative to interface with a pneumaticpiston 102 a. A motor rotates the piston 97 a to allow operation of thepacking plate 113.

The food-zone cover apparatus 93 further includes a plurality offeatures 99, 101 in the cover 90 operative to interface with pneumaticpistons to hold the food-zone cover apparatus 93 against the rotatingfreeze surface 70 a. More specifically, depression 99 located on theperiphery of the top 90 c of cover 90 interfaces with hold down piston99 a. Similarly depression 101, also located on the periphery of the topof cover 90 but, when viewed from above, angularly displaced relative todepression 99, interfaces with hold piston 101 a.

With further reference to FIG. 23, the illustrated food-zone coverapparatus 93 further includes a mix-ins receiving port 108 coupled tothe cover 90. The port 108 receives mix-ins from the dispensing orifice73 of the mix-ins trough and distributes the mix-ins onto the liquidproduct after the level 94 has leveled the liquid food product onto therotary freeze surface 70 a.

Flavor-Selection Assembly/Flavor Wheel

With reference to FIGS. 32-34, one embodiment of a flavor-selectionassembly 208 includes a pump motor 210 connected to a pulley assembly212. The pulley assembly 212 includes a driving gear 212 c coupled by abelt 212 b to a driven gear 212 a. The driven gear 212 a in turn couplesvia shaft 214 a to a flavor-distribution-wheel assembly 214. Theflavor-distribution-wheel assembly 214 includes a wheel 214 c with aplurality of fittings 214 b, which form a plurality of nozzles 216 a,216 b. In the illustrated embodiment, there are twelve nozzles in thewheel 214 c; each nozzle is adapted to connect via tubing to anassociated displacement pump 50 in the flavor module 14 described above.The flavor-distribution-wheel assembly 214 further includes an outlet218 that couples to a common flavoring outlet conduit. With reference toFIGS. 32-34, the center 215 of the flavor wheel 214 c has a channel 211(shown in FIG. 33).

The flavor-selection assembly 208 further includes a sub-controller 209and a conventional sensor 213 coupled to the sub-controller 209. Thesub-controller 209 receives signals from the sensor 213 and controlsmotor 210 to position the flavor wheel 214 c in a home position, e.g.,rotating the flavor wheel 214 c to align the channel 211 so that it isbetween two nozzles (such as nozzles 216 a and 216 b). In this position,no flavor can pass through to outlet 218.

In operation, each flavor enters the flavor wheel 214 c via one of theplurality of nozzles (e.g., nozzles 216 a, 216 b). When the systemreceives a flavor selection signal, the main controller instructs theflavor wheel sub-controller 209, via bus 209 a, to drive motor 210 torotate channel 211 a specified amount to bring channel 211 intoalignment with the nozzle associated with the selected flavor, therebyallowing the flavor in the aligned nozzle to flow through to outlet 218.

A fitting 217 also sits on top of shaft 214 a to receive compressed airfor cleaning out the outlet 118 and the outlet conduit. As shown in FIG.37, in one embodiment, the flavor-selection assembly 208 resides in aprocess box 24 that sits above the food-zone cover apparatus 93 and thefood-preparation assembly 22 (shown in FIG. 1).

Conduit Assembly

With reference to FIG. 36, one embodiment of a conduit assembly 120includes a proximal end 120 a and a distal end 120 b. The proximal endincludes a crow's foot junction 122 having three inlets 121, 123, and125 and an outlet 122 a. The first inlet 121 couples to a conduit, notshown, that in turn connects to conduit 32 via bulkheadconduit-to-conduit union 33 (see FIG. 3). In other words, the firstinlet 121 receives a first base mix via a conduit line attached to afirst base mix container held in a first base mix tray 30 a in thebase-mix module 12 of FIGS. 2 and 3. Similarly, the third inlet 125receives a second base mix via a conduit line attached to a second basemix container held in the second base mix tray 30 b in the base-mixmodule 12. The second inlet 123 couples via a one-way valve 129 and viatubing to a pneumatic module 242 (shown in FIG. 41) for receiving air.The crow's foot junction 122 couples via a female luer lock 141 totubing 120 c.

One embodiment of the conduit assembly's distal end 120 b includes abarbed rotating male luer lock adaptor 139 coupled to the distal end oftubing 120 c. The adaptor 139 couples to a female luer lock 131. Thelock 131 couples to a first inlet of a two-inlet, one-outlet teeconnection 137. The second inlet couples via a male luer lock 135 tofood grade tubing 133, which in turn couples to the output of theflavor-selection assembly 208 of FIGS. 32-34. The outlet of the teeconnection 137 couples via tubing 136 to mixing conduit 127. Thisconfiguration allows the conduit assembly 120 to combine base mix, airand flavoring to produce a flavored, aerated mix at the output of mixingconduit 127. In one embodiment, flavored aerated mix is ejected from adistal end of mixing conduit 127 onto the rotating freeze surface 70 aof the food-surface assembly 70 shown in FIGS. 15 to 19. Morespecifically, with reference to FIGS. 23 and 24, the conduit assembly120 couples to the food-zone cover apparatus 93 and sprays the mix fromend 92 a onto the rotating freeze surface 70 a. Element 92, shown inFIG. 23, is the same as mixing conduit 127 shown in FIG. 36.

Process Box

With reference to FIGS. 37-47, which illustrate components in a processbox, one embodiment of the process box 24 includes a conventionalelectrically operated pneumatic solenoid pump bank 232 (shown in FIG.39), such as those available form SMC Corporation of America ofIndianapolis, Ind. In one embodiment, the solenoid pump bank 232includes an air inlet 231 and a plurality of, e.g., seven, air outlets233 a, 233 b. The air inlet 231 couples to a conventional pneumaticmodule 242, such as a Gast compressor system available from OhlheiserCorporation of Newington, Conn., USA. The pneumatic module 242 providesregulated compressed air, e.g., at about 80 psi, to the air inlet 231 ofthe pump bank 232.

As noted above with respect to the food-zone cover apparatus 93, theprocess box 24 further includes a plurality of, e.g., seven,pneumatically driven piston assemblies 97 b, 99 b, 101 b, 102 b, 103 b,105 b, 107 b. Each assembly has a piston 97 a, 99 a, 101 a, 102 a, 103a, 105 a, 107 a coupled to a pneumatic cylinder 97 c, 99 c, 101 c, 102c, 103 c, 105 c, 107 c. Each pneumatic cylinder couples to an air outputof the solenoid pump bank 232. The solenoid pump bank 232 distributesair pressure to the pneumatic cylinders to operate the pistonassemblies. Each piston 97 a, 99 a, 101 a, 102 a, 103 a, 105 a, 107 ainteracts with an associated piston interface 97, 99, 101, 102, 103,105, 107 on the food-zone cover 90. As noted above, a conventionalpneumatic module 242 couples to the air inlet of the solenoid pump bank232 and provides compressed air to the solenoid pump bank 232 so thatthe solenoid pump bank 232 can manage operation of the piston assemblies97 b, 99 b, 101 b, 102 b, 103 b, 105 b, 107 b to control interaction ofthe pistons 97 a, 99 a, 101 a, 102 a, 103 a, 105 a, 107 a withassociated piston interfaces 97, 99, 101, 102, 103, 105, 107 on thefood-zone cover 90.

With reference to FIG. 41, the pneumatic module 242 includes a holdingtank 246 that provides food grade air to an air compressor 244. The aircompressor 244, in turn, provides compressed air to a first regulator248 and to a second regulator 250. The first regulator 248 providesregulated air at a specified pressure, e.g., 80 psi, to the solenoidpump bank 232 in the process box 24. The second regulator 250 providesfood-grade air at a specified pressure, e.g., 40 psi, to the conduitassembly 120.

Packing-Plate Piston Assembly

Having described the process box 24 in general, with reference to FIGS.42 and 43, one embodiment of a packing-plate piston assembly 102 blocated in the process box 24 includes a post 274 coupled to a base 276.The post 274 couples to a proximal end of an arm 268 via a pin 270. Acylinder 102 c couples to the base 276 and to a midsection of the arm268 so as to raise and lower the arm 268. A distal end of the arm 268couples to a piston shaft 266 via a shaft end 272. Thus, actuating thecylinder 102 c lowers the shaft 266. A gear 264 slides onto the shaft266 and affixes to the shaft 266 in a concentric arrangement. Thepacking-plate piston assembly 102 b further includes a motor 260, whichdrives a pinion 262. The driven pinion 262, in turn, drives gear 264 torotate the piston shaft 266.

Thus, with reference to FIGS. 42, 43 and 23, in operation, theprocess-box sub-controller actuates the cylinder 102 c to lower thepiston shaft 266, which engages piston 102 a with piston interface 102.The process-box sub-controller then energizes motor 260 to rotate thepiston shaft 266, which in turn rotates packing plate 113 to operate thepacking plate 113.

Packing-Piston Drive Assembly

With reference to FIGS. 44 and 45, one embodiment of a packing-pistondrive assembly 97 b located in the process box 24 includes a cylinder 97c mounted on a bracket 284, which in turn is mounted on a bottom plate286. The packing-piston drive assembly 97 b also includes a piston guide288 that also mounts on the plate 286 so as to cover orifice 292. A topplate 290 attaches to cylinder 97 c and guide 288. The packing piston 97a slidably engages with the bottom plate 286 and with guide 288 viaorifice 292. Attached to the cylinder 97 c is a sliding cylinder plate280. Attached to the cylinder plate 280 is piston-attachment plate 282,which also attaches to piston 97 a. Thus, when the process-boxsub-controller actuates the cylinder 97 c, the cylinder 97 c drives thepiston 97 a down to interact with interface 97 to operate the diaphragm160 (described above with respect to the food-zone cover 90). In oneembodiment, pin 290 (shown in FIG. 38) engages with slot 97 b (shown inFIG. 29).

Rack-and-Pinion Drive Assembly

With reference to FIGS. 46 and 47, one embodiment of a rack-and-piniondrive assembly 107 b located in the process box 24 includes a post 294coupled to a base 296. The post 294 couples to a proximal end of an arm298 via a pin 297. A cylinder 107 c couples to the base 296 and to amid-section of the arm 298 so as to raise and lower the arm 298. Adistal end of the arm 298 couples to a piston shaft 107 a via a shaftend 295. Actuating the cylinder 107 c lowers the piston shaft 107 a. Agear 291 slides onto the shaft 107 a and affixes to the shaft 107 a in aconcentric arrangement. The rack-and-pinion drive assembly 107 b furtherincludes a motor 289, which drives a pinion 293. The driven pinion 293in turn drives gear 291 to rotate the piston shaft 107 a.

Thus, with reference to FIG. 46, in operation, the process-boxsub-controller actuates the cylinder 107 c to lower the piston shaft 107a, which engages with piston interface 107. The process-boxsub-controller then energizes motor 289 to rotate the piston shaft 107a, which in turn rotates pinion 110 a to operate the plow 100 (pinion110 a and plow 100 are shown in FIG. 25).

The other four piston assemblies, i.e., 99 b, 101 b, 103 b, 105 b, areconventional piston assemblies

Primary Refrigeration System

With reference to FIG. 48, one can describe the architecture of oneembodiment of the primary refrigeration system 300 for thefood-preparation assembly 22 by describing the loop(s) through whichrefrigerant travels during various modes of operation of the primaryrefrigeration system 300 under the control of the apparatus controlleror a sub-controller governed by the apparatus controller. Thecontrollers and sub-controllers of this apparatus can each includesoftware stored on a computer-readable medium that is coupled with aprocessor; the software includes code for generating instructions forthe components, described below, to carry out the various processesconsequent to appropriate input being sent to the controller andsub-controllers.

Cooling

During cooling, i.e., when the primary refrigeration system 300 bringsthe food-surface assembly 70 down from ambient temperature to a setpoint, a cooling loop starts when the apparatus controller sends aninstruction to the compressor 326 to start pumping to start therefrigerant gas flowing from the compressor 326 via a compressordischarge line 306 to a condenser 302. Stated differently, thecompressor 326 discharges refrigerant in the form of relatively hot andhigh-pressure gas into the condenser 302. The controller also sends aninstruction to start a fan that blows ambient air over the condenser 302transferring heat in the gas to the ambient air; the fan blows theambient air out of the unit. By cooling the hot gas, the hot gas ischanged into a warm liquid. Under normal operation, the controller keepsa defrost solenoid 310 (an alternate loop) closed, which sends all ofthe refrigerant through the condenser 302.

The liquid flows from the condenser 302 into a receiver 304, whichstores liquid for the refrigeration system 300. The liquid flows througha filter drier 308, which removes particulates, acid and moisture fromthe refrigerant. Then the liquid flows through a coil situated in thebottom of the suction accumulator 324. The warm liquid in the coil boilsoff any liquid coming into the suction accumulator 324 via suction line323.

The liquid then flows from the suction accumulator 224 through a liquidsolenoid 311, which is governed by the controller to provide on/offcontrol to a liquid thermal-expansion (TX) stepper valve 312. The main(apparatus) controller, using a control algorithm with a wet/drythermistor 326 as an input, controls the liquid flow into thefood-surface assembly 70. As noted above, the apparatus controllercommunicates via a bus to sub-controllers using a protocol such as theCANOpen protocol. In one embodiment, the primary-refrigeration-systemsub-controller includes digital I/O board with an CANOpen gateway andtwo analog I/O boards. The sub-controller further includes first andsecond stepper controller boards daisy-chained to the digital I/O board.The controller and sub-controllers are also coupled (e.g., via wires orvia wireless communication equipment) with each of the various sensorsand control mechanisms in the system 300.

The sub-controller feeds an excess of liquid into the food-surfaceassembly 70, which keeps the wet/dry thermistor 326 at the food-surfaceassembly exit wet, i.e., the refrigerant passing the thermistor 326 isat least partially in a liquid state. As the liquid refrigerant passesthrough the food-surface assembly 70, it boils, cooling the food-surfaceassembly 70. More specifically, when the refrigerant passes through theliquid-stepper expansion valve 312, the refrigerant experiences apressure drop that turns the liquid into a cold liquid with some gas.The system injects the refrigerant in this state into the food-surfaceassembly 70, where the cold liquid chills the food-surface assembly 70.In the process of cooling the food-surface assembly 70, much of theliquid boils off into a gas. The liquid and gas mixture leaves thefood-surface assembly 70 and passes through the suction accumulator 324.The excess liquid collects in the bottom of the accumulator 324 where itis boiled by the warm liquid coil. The refrigerant gas leaves theaccumulator 324 and returns to the compressor 326.

More specifically, the liquid stepper valve 312 is a conventionalelectronically controlled needle valve. The liquid stepper valve 312passes the liquid refrigerant, via a liquid stepper discharge line 313and via a rotary coupling 314 a, into the food-surface assembly 70. Athermocouple 318 facilitates measurement of the temperature of thefood-surface assembly 70. The refrigerant then exits the food-surfaceassembly 70 via a rotary coupling 314 b and travels back to suctionaccumulator 324 via a food-surface assembly discharge line 321. In theillustrated embodiment, the discharge line 321 has a serpentine section325 having a length of about 8 feet or more with a plurality of turns,e.g., four to eight bends. A pressure transducer 320 measures thepressure just prior, i.e., just upstream, to the serpentine section 325.The thermistor 326, mentioned above, measures the temperature in thedischarge line on the downstream side of the serpentine section 325. Inone embodiment, the primary refrigeration system 300 uses a conventionalrefrigerant, such as R404A. However, the primary refrigeration systemcan use other refrigerants, such as R507.

After a period of time, the food-surface assembly 70 temperature sensor(e.g., thermocouple 88) measures that the food-surface assembly 70 hasreached a set point. The thermocouple 88 communicates this reading tothe sub-controller, which is programmed with software stored on acomputer-readable storage medium. The processor in the controller, whenprocessing this code in combination with the reading from thethermocouple 88, initiates operation of a temperature-control loop.

Temperature Control

In order to artificially reduce the cooling capacity of the cooling loop(to maintain the set-point temperature), the controller causes a falseload to be introduced. Thus, with reference to FIG. 49, the controller,in addition to governing the cooling loop (the inner loop, shown as loop1), also governs a temperature-control loop (the outer loop, shown asloop 2), wherein hot gas from the compressor discharge line is sentthrough a hot-gas solenoid 327. The hot gas then travels through ahot-gas stepper valve 322 (a proportionally controlled valve) and entersthe cooling loop (loop 1) at a point 323 proximate to the beginning ofthe serpentine section 325. In the illustrated embodiment the hot gasfrom the hot-gas stepper valve 322 enters the food-surface assemblydischarge line 321 downstream from the location of the pressuretransducer 320. The controller governs the hot-gas stepper valve 322 tocontrol the amount of hot gas that passes into the food-surface assemblydischarge line 321.

A hot-gas valve control scheme controls on temperature. If thetemperature of the food-surface assembly 70, as measured by thermocouple88, is below the set point, the controller sends an instruction to thehot-gas valve 322 to open by an amount that is proportional to how farthe temperature of the food-surface assembly 70 is below the set pointand proportional to how long the temperature of the food-surfaceassembly 70 has been below the set point. The software run by thecontroller utilizes a Proportional Integral and Derivative (PID) loop.Thus, the temperature-control loop (loop 2) applies a false load to thecompressor 326 reducing the capacity of the cooling loop to cool thefood-surface assembly 70.

Modes/Control States

Pull Down

The controller governs the primary refrigeration system 300 to operatein a variety of modes. In pull-down mode, the mode in which thetemperature of the food-surface assembly 70 is brought down from ambienttemperature to a set point, the controller sends commands to therefrigeration system 300 to bring the temperature of the food-surfaceassembly 70 to the temperature that is needed to make ice cream. In oneembodiment, the goal for pull-down mode is to achieve the set-pointtemperature, e.g., 12 degrees Fahrenheit, to within plus or minus onedegree for 30 seconds. The pull-down modes starts with the hot-gas valve322 in the off position, the liquid stepper valve 312 is at a boostedset point, e.g., about 280 steps where the valve 312 ranges from 0 to380 steps (380 steps being completely open). Once the system is within aspecified range, e.g., within 10 degrees, of the set-point temperature,the controller sets the liquid stepper valve 312 to a normal set value,e.g., 135 steps.

Idle/Standby

Once the system achieves the set point to within plus or minus onedegree for 30 seconds, the controller (based on the communication of thetemperature to it) instructs the system to transition from pull-downmode to idle mode. Idle mode is a mode in which the system is ready tomake food product, e.g., ice cream. Once the system starts sprayingliquid onto the food-surface assembly 70, within less than a ten secondinterval, the primary refrigeration system 300 sees a large heat loadbecause the primary refrigeration system 300 changes the state of thesprayed material from a liquid (mostly water) to an at least partiallyfrozen food product, e.g., ice cream. In other words, in one embodiment,the primary refrigeration system 300 freezes a serving's worth of water,which involves a change of state of the water, requiring a large amountof energy in a very short period of time relative to maintaining thetemperature of the food-surface assembly 70 in an idle state.

Once, in idle mode, the controller no longer controls the system basedon a direct measurement of the temperature of the food-surface assembly70. Rather, the controller controls based on readings communicated tothe controller from the pressure transducer 320.

The pressure transducer 320 is used to determine the refrigeranttemperature in the food-surface assembly 70. The refrigerant for anygiven pressure only boils at one temperature. So if one measures thepressure in the food-surface assembly discharge line, then one candetermine the temperature of the refrigerant. Pressure/temperaturecurves for various refrigerants, such as R404A and R507, are well knownand readily obtained. The controller also controls the hot-gas steppervalve 322 based on readings received from the pressure transducer 320rather than on readings from the thermocouple 88 because of thesensitivity of the temperature of the food-surface assembly 70 to thefood product when food product is placed on the food-surface assembly 70during an ice-cream-making mode.

The control scheme is self-correcting. Once the primary refrigerationsystem 300 transitions into idle mode, the controller determinessaturation temperature, the boiling temperature of the refrigerant,based on the first measurement of pressure by the pressure transducer320. The controller then uses that saturation temperature as a setpoint.

The controller controls transition from pull-down mode to idle mode andcontrols the hot-gas valve 322 in idle mode in an effort to directlycontrol the temperature. In contrast, the controller controls the liquidthermal-expansion stepper valve 312 so that the thermistor 326 indicatesthat the refrigerant is in a wet state, i.e., the refrigerant passingthe thermistor 326 is at least partially in a liquid state.

In one embodiment, the controller causes flooding of the food-surfaceassembly 70 so that the system has excess liquid at the exit from thefood-surface assembly 70. Flooding the food-surface assembly 70 ensuresthat the food-surface assembly 70 is fully active with refrigerantboiling across the whole food-surface assembly 70. To achieve a floodedfood-surface assembly 70, the controller monitor readings from thethermistor 326 to monitor the state of the refrigerant.

More specifically, in order to maintain the refrigerant in a wet state,the controller evaluates the resistance across the thermistor 326periodically, e.g., every thirty seconds, and controls the liquidstepper valve 312 in response to those measurements. The thermistor 326is a a type of resistor used to measure temperature changes, relying onthe change in its resistance with changing temperature.

If one assumes that the relationship between resistance and temperatureis linear, then one can state the following:ΔR=kΔT

where

ΔR=change in resistance

ΔT=change in temperature

k=first-order temperature coefficient of resistance

When the refrigerant transitions from a dry state to a wet state, itbecomes colder. Assuming k is positive, when the temperature of therefrigerant becomes colder, the resistance measured by the thermistor326 drops. Assuming a constant current source, a drop in thermistorresistance results in a voltage drop across the thermistor 326. In oneembodiment, a refrigerant dry state is defined as corresponding to a5-volt drop, and a refrigerant wet state is defined as corresponding toa 2-3 volt drop. Thus, the controller monitors readings from thethermistor 326 periodically, e.g., every 30 seconds, and if thethermistor voltage drop does not indicate a wet state, the controlleradjusts the liquid stepper valve 312 in an attempt to return therefrigerant to a wet state.

Stated differently, the controller uses the liquid stepper valve 312 tocontrol the quantity of liquid at the wet/dry thermistor 326 to keep thefood-surface assembly 70 flooded. When the liquid stepper valve 312opens up, it increases the quantity of refrigerant in the system, whichin turn raises the pressure in the food-surface assembly discharge linemeasured by the pressure transducer 320, which in turn changes thetemperature, which causes the hot-gas valve 322 to react. Thus, theliquid stepper valve 312 and hot-gas valve 322 systems areinterdependent.

When a system designer designs a typical refrigerant system, generallythe designer does not care much about where the position of liquidrefrigerant is in the system, other than not wanting it in thecompressor 326. Other than that, all a designer is typically trying todo is to maintain some temperature in some environment.

In the present invention, it is helpful to maintain the food-surfaceassembly 70 in a flooded state. In other words, in one embodiment, thesystem attempts to ensure that at least some refrigerant remains inliquid state during the refrigerant's path through the serpentinechannel in the food-surface assembly 70.

Maintaining the food-surface assembly 70 in a flooded state hasadvantages. When a temperature change of a liquid, e.g., refrigerant,involves boiling, i.e., the state transition of a liquid to a gas, thetemperature change involves a large energy transfer relative to asimilar temperature change not involving a state transition. Bymaintaining the refrigerant in a liquid state, the controller maintainsthe ability to have a relatively large influence on the temperature ofthe food-surface assembly 70 in a relatively short amount of time.

In addition, maintaining a flooded state helps maintain temperaturestability across the entire rotating freeze surface 70 a [e.g., oneembodiment of the food-surface assembly 70 has a 19-inch diameter(48-cm) freeze surface], and it provides the controller with relativelyprecise control of the temperature because the controller does not needto adjust the system for the possibility that the refrigerant might turncompletely to gas in the evaporator/food-surface assembly 70; therefrigerant is always in an at least partially liquid state. In oneembodiment, the controller maintain the temperature in the primaryrefrigeration system within +/−1 degree Fahrenheit (F) (+/−0.55° C.) andmaintains uniformity of the temperature across the freeze surface 70 ato within +/−1° F.

As noted above, when the system 300 first enters pull-down mode, thecontroller sets the liquid valve at a boosted set value, e.g., 280 stepsin a range of 0-380 steps. Once the system is within a specified range,e.g., within 10 degrees, of the set-point temperature, the controllersets the liquid valve to a normal set value, e.g., 135 steps. Once thesystem transitions into idle mode, the controller adjusts the liquidvalve setting to maintain the refrigerant at the thermistor 326 in a wetstate.

Making Ice Cream

When the system 300 is in idle mode, it is ready to make ice cream. Withreference to FIG. 53, at state 0, a user indicates via user controls,e.g., a graphical user interface, that the user wants the unit to make aselected ice cream serving. In response, after a predetermined amount oftime and before, the controller generates instructions to cause thespraying of food product onto the food-surface assembly 70; and the maincontroller enters a pre-cold stage, state 1. The food product is only onthe food-surface assembly 70 for about ten seconds. At state 1, the maincontroller shuts down the hot-gas valve 322 and sets the liquid valve312 to the boosted set value, e.g., about 280 steps. At state 2, thefood product is sprayed onto the food-surface assembly 70. At state 3,the food product, now in the form of frozen food product, e.g., icecream, leaves the food-surface assembly 70.

Once the food product leaves the food-surface assembly 70, thecontroller monitors the temperature of the food-surface assembly 70. Thecontroller transitions the system 300 to the next state, state 4, oncethe temperature of the food-surface assembly 70 is below thefood-surface assembly temperature set point, e.g., 12° F. (−11° C.). Ifthe food-surface assembly temperature is below the set point when thefood product comes off the food-surface assembly 70, then the controllerautomatically transitions the system to state 4. Otherwise, thecontroller waits until the temperature of the food-surface assembly 70is below the set point to intitiate the transition. The controller pollsthe thermocouple 88 periodically to monitor the food-surface assemblytemperature, e.g., every 100 ms+/−30 ms, to determine when to maketransitions that depend on the temperature of the food-surface assembly70. At the transition, the controller sends an instruction to thehot-gas valve 322 to open to the value it had at state 0. Apredetermined amount of time is taken for the hot-gas valve 322 toachieve the state 0 value. When the hot-gas valve 322 achieves the state0 value, the controller transitions the system to state 5.

The controller transitions the system to the next state, state 6, whenthe controller determines, by monitoring the pressure transducer 320,that the saturation temperature has recovered (e.g., when the saturationtemperature is greater than or equal to the original saturationtemperature set point plus some predetermined amount). Once the systemis transitioned to state 6, the controller instructs the liquid steppervalve 312 to return to the value it had at state 0, the state 0 value ornormal set point value (e.g., about 130 steps). As with the hot-gasvalve 322, a predetermined amount of time is utilized for the liquidstepper valve 312 to achieve the normal set-point value.

As noted above, the main controller communicates with sub-controllersincluding the primary-refrigeration-system sub-controller using aprotocol such as the CANOpen protocol. One can refer to eachsub-controller or module with which CANOpen communicates as a node.There are stepper controllers for the hot-gas valve 322 and for theliquid thermal-expansion valve 312. There are different processesrunning on the host computer that will tell each different node what todo.

In one embodiment, the program that controls the main controller iswritten in the C programming language and follows the CANOpenspecification to achieve communication with sub-controllers includingthe primary-refrigeration-system sub-controller.

Defrost Loop/Mode

With reference to FIG. 50, the defrost loop begins with refrigerant gasflowing from the compressor 326 through the discharge line 306 to thedefrost solenoid 310. The defrost solenoid 310 couples the compressordischarge line 306 with the liquid stepper discharge line 313. Thedefrost mode thaws the food-surface assembly 70 out. In other words, indefrost mode the system raises the food-surface assembly temperature sothat the food-surface assembly 70 can be cleaned. During defrost mode,the main controller closes the liquid solenoid 311 and the hot-gassolenoid 327 so there is no flow down the cooling loop and thetemperature-control loop. The defrost solenoid 310 is open sorefrigerant gas, which is hot from the compressor, is directed into thefood-surface assembly 70. The hot refrigerant gas returns throughsuction line 323 and through the suction accumulator 324 back to thecompressor 326. Thus, the defrost loop provides a loop of warm gas thatflows through the food-surface assembly 70 warming the food-surfaceassembly 70 to a defrost set-point temperature. Over a period of time,e.g., three to five minutes, the food-surface assembly 70 warms up, whenthe food-surface assembly thermocouple 88 determines that thefood-surface assembly 70 has reached a set point, e.g., 48 degreesFahrenheit, the main controller terminates defrost mode and turns thedefrost solenoid 310 off. Once the food-surface assembly 70 portion ofthe food-preparation assembly 22 has reached the defrost set-pointtemperature, an operator can then clean the food-surface assembly 70 andassociated areas, e.g., the operator can wipe down the rotary freezesurface 70 a.

Depending on the requirements of the user of a system according to theinvention, the user can instruct the system via user controls, e.g., agraphical user interface, to enter the defrost mode periodically, e.g.,once a day typically at the end of the day.

Controls

With reference to FIG. 51, the primary refrigeration system 300 includesa hot-gas valve sub-controller 328 for controlling the temperature ofthe food-surface assembly 70. As noted above, the sub-controller 328monitors the surface temperature of the food-surface assembly 70 viathermocouple 318 and the suction pressure via pressure transducer 320.

With reference to FIG. 52, the primary refrigeration system 300 includesa liquid stepper control 330 for controlling the flow of liquidrefrigerant into the food-surface assembly 70. As noted above, thecontrol 330 monitors thermistor 326 and opens and closes the liquidstepper valve 312 to keep the thermistor 326 in what is referred to as a“wet zone.”

Control States

In one embodiment, the control states for the primary refrigerationsystem 300 are the following: initialization; stopped; pull down(startup); standby; ice cream cycle (7 steps); defrost; fault; andoverride/diagnostics.

“Initialization” is the process of turning the machine on. “Stopped”involves stopping the primary refrigeration system. “Pull down” occurswhen the food-surface assembly 70 is above the set-point temperature,e.g., at ambient temperature, and the primary refrigeration system pullsthe food-surface assembly 70 down to the set point. In one embodiment,the pull down process from room temperature takes about twenty minutes.

The primary refrigeration system 300 uses conventional proportionalintegral and derivative control. Proportional integral and derivativecontrol is a form of control appropriate for a system that cannot movefrom a given environmental condition to the set point simply as a stepfunction. In other words, proportional integral and derivative controlis a form of control appropriate for a primary refrigeration system thatcannot move the food-surface assembly 70 from 85° F. (29° C.) linearlyand directly to 12° F. (−11° C.). Proportional integral and derivativecontrol typically achieves a set point via a sinusoidal closed wavefunction. A primary refrigeration system using proportional integral andderivative control and having a 12° F. (−11° C.) set point starts withthe food-surface assembly 70 at ambient temperature, e.g., 85° F. (29°C.). The temperature of the food-surface-assembly 70 starts coming down.The food-surface-assembly temperature passes below the set point, e.g.,12° F. (−11° C.). The food-surface-assembly temperature then oscillatesup and down around the set point. Thus, the temperature of thefood-surface assembly 70 as a function of time resembles a dampenedharmonic oscillator oscillating around the set-point temperature. Theamplitude of the oscillations becomes smaller and smaller and eventuallythe wave dampens itself out.

The idle/standby, ice cream cycle/making, and defrost states/modes weredescribed above. The other states are conventional states used incontrolling food preparation machines.

With reference to FIG. 54, many of the elements of the primaryrefrigeration system are conventional. The following is a list of partsand associated manufacturers and suppliers for one embodiment of theprimary refrigeration system.

Supplied DCI Lydall Item Description Manufacturer Part number By Part #Part # 326, Condensing Tecumseh AWA2464ZXDXC DCI 61872 302 & Unit 304308 Filter drier Sporlan C-083-S Lydall 61872 9476 329 Sight glassSporlan SA13S Lydall 68119 2546 312 TX valve Emerson Flow ESVB-1 24 DCI61873 Control Connector, Alco 62093 DCI 61874 stepper, 4 wire for TX 322Hot-gas valve Sporlan SEI 11 3X4 ODF- Lydall 72525 13072 10-S 324Suction Refrigeration HX 3738 Lydall 72529 32660 accumulator Research326 Thermistor Parker 040935-04 DCI 72539 Adapter 7/8 Thermistor Parker040930-150 DCI 72537 310 Solenoid Sporlan E5S130 Lydall 33101 valve 1-Defrost Solenoid coil Sporlan MKC1-208- DCI 74169 240/50-60 331 5/8 Ballvalve Various Lydall 72890 6095 refrigeration grade 333 7/8 Ball valveVarious A17264 Lydall 74004 6096 refrigeration grade 314A 5/8 TubeParker 12-10L0HB3-S DCI 72639 fittings (2) Liquid hose Parker 73499 DCI73499 314B 5/8 Tube Parker 12-10L0HB3-S DCI 72639 fittings (2) Suctionhose Parker 73501 DCI 73501 321 Suction line Lydall 32722 Lydall 7401332722 mixing line 7/8 323 Suction riser Lydall 32724 Lydall 74012 327247/8 335 Suction line Lydall 32723 Lydall 74009 32723 7/8 320 PressureMSI MSP-300-250-P-4- DCI 73021 transducer N-1 327 Solenoid Sporlan B6S1Lydall 33102 valve 2-Hot 1/2ODFx5/8ODM gas 311 Solenoid Sporlan E5S130Lydall 33101 valve 3-Liquid 337 Pressure Emerson Flow PS1-X5K Lydall5704 switch Control Refrigerant Lydall 74016 28124 R404a

DCI is DCI Automation, Inc. of Worcester, Mass. Lydall is Lydall, Inc.of Manchester, Conn. Tecumseh is Tecumseh Products Company of Tecumseh,Mich. Sporlan is Sporlan Valve Company of Washington, Mo. Parker is theclimate and industrial controls group of Parker Hannifin Corporationlocated in Broadview, Ill. Emerson Flow Control is the flow controlsdivision of Emerson Climate Technologies of St. Louis, Mo. RefrigerationResearch is Refrigeration Research, Inc. of Brighton, Mich.

Timing Diagrams

Having provided an overview of the structure and operation of the unit200, shown in FIG. 1, and having described the structure and operationof the components that make up that unit, a description of the timingdiagrams provided in FIG. 55 for various system sequences is nowprovided. Each of the timing diagrams lists the following items (andoperational state) on the vertical (y) axis: 1^(st) cover hold-down(up/down); 2^(nd) cover hold-down (up/down); packing plate engagement(up/down); packing plate position (delivery/forming/home); pinionengagement (up/down); horizontal pinion drive (forward/back/home);vertical forming piston (up/neutral/down); cup lift (up/neutral/down);leveling squeegee cleaning (up/down); leveling squeegee downforce(up/down); base pump (running/stopped); aeration (on/off); flavor pump(running/stopped); flavor purge (on/off); and mix-in motor(running/stopped). The horizontal (x) axis denotes time. Thus, thetiming diagrams indicate the time of state transitions during varioussystem activities for the items listed on the vertical axis.

The labels, “cover hold-down #1,” “cover hold-down #2,” “packing plateengagement,” “packing plate position,” “pinion engagement,” “horizontalpinion drive,” “vertical forming piston,” “cup lift,” “leveling squeegeecleaning,” and “leveling squeegee downforce,” refer to the up/down orengagement state of the pistons shown in FIGS. 37-40 and 42-47. The maincontroller, via the process sub-controller, controls the pump bank andpiston assembly motors to achieve the desired states. Similarly, thelabels, “base pump,” “aeration,” “flavor pump,” “flavor purge,” and“mix-in motor,” respectively refer to the on/off or running/stoppedstates of the base pump, the food grade portion of the pneumatic module,the flavor pump, the flavor purge portion of the pneumatic module, andthe mix-ins motor. The main controller either directly and/or viavarious component sub-controllers controls the states of thesecomponents.

With reference to FIG. 55, one embodiment of a sequence for serving foodproduct, e.g., ice cream, starts in the following state: cover hold-down#1 (down); cover hold-down #2 (down); packing plate engagement (down);packing plate position (forming); pinion engagement (down); horizontalpinion drive (back); vertical forming piston (up); cup lift (down);leveling squeegee cleaning (up); leveling squeegee downforce (up); basepump (stopped); aeration (off); flavor pump (stopped); flavor purge(off); and mix-in motor (stopped). A variety of conventional sensorsdetermine that the food service machine proceeds through the followingprocess prior to initiating the serving sequence: delivery doorinterlock (disengaged); delivery door sensor (open); user installs cup;cup sensor (yes); delivery door sensor (closed); deliver door interlock(engage); and start freeze surface rotation.

The illustrated serving sequence is the following, each numbered stepoccurring later in time than the prior numbered step: 1) at time TS2 theleveling squeegee moves down; 2) the base pump starts running, and theaeration is turned on; 3) the flavor pump starts running (at this point,the mixing conduit is spraying a mixed, aerated composition (typicallyflavored mix onto the rotating freeze surface); 4) the mix-in motorstarts running (causing the mix-ins module 16 to deposit selectedmix-ins onto the leveled food product sitting on the rotating freezesurface); 5) the base pump stops; 6) the flavor pump stops, and theflavor purge is turned on; 7) the flavor purge ends, and the aerationends; 8) the mix-in motor stops; 9) the leveling squeegee downforcepiston disengages (moves up); 10) the leveling squeegee cleaning pistonmoves down to cause cleaning of the squeegee; 11) the leveling squeegeecleaning piston moves up, the cup lift moves up, and the freeze surfacestops rotating (the food product is now accumulated as a ridge row onthe scraper of the food zone cover); 12) the horizontal pinion drivemoves to the forward position (pushing the food product into the formingcylinder); 13) the vertical forming piston moves down (to pack the foodproduct); 14) the vertical forming piston moves to a neutral position;15) the packing plate position moves from forming to delivery; 16) theproduct deposits into a cup; 17) the cup lift moves from up to neutralposition; 18) the packing plate position moves from delivery to forming;and 19) a variety of conventional sensors determine that the foodservice machine proceeds through the following process: (a) deliverydoor interlock (disengage); (b) delivery door sensor (open); (c) theuser removes the cup; (d) cup sensor (clear/no cup); (e) delivery doorsensor (close); and (f) delivery door interlock (engaged). The servingsequence completes with the following steps: 20) the packing plateposition moves from forming to home and then to delivery to achieve awiping action and the vertical forming piston moves from down to up; 21)the horizontal pinion drive moves from forward to home and then, after aperiod, to back position; 22) the vertical forming piston moves from upto down and then, after a period, to up position again; 23) finally, thepacking plate position moves from delivery to forming.

Having thus described at least one illustrative embodiment of theinvention, various alterations, modifications and improvements arecontemplated by the invention. Such alterations, modifications andimprovements are intended to be within the scope and spirit of theinvention. Accordingly, the foregoing description is by way of exampleonly and is not intended as limiting. The invention's limit is definedonly in the following claims and the equivalents thereto.

1. Apparatus for producing a food product, the apparatus comprising: aframe; a base-mix module coupled to the frame and operative to provide abase mix; a flavor module coupled to the frame and operative to provideflavoring; a flavor-selection assembly coupled to the frame and havingan outlet and a plurality of flavoring inlets, each inlet operative toreceive a flavoring, the flavor selection assembly operative to allowpassage of a flavoring from an inlet to the outlet; a conduit assemblyhaving a proximal end including a first opening coupled to the base-mixmodule and a second opening for receiving air, the conduit assemblyhaving a distal end coupled to the outlet of the flavor-selectionassembly, the conduit assembly operative to combine base mix, air andflavoring to produce a flavored aerated mix; a food-preparation assemblycoupled to the frame and configured to receive the flavored, aerated mixfrom the distal end of the conduit assembly and to prepare food from theflavored aerated mix; and an apparatus controller in communication witheach of a plurality of sub-controllers and operative to provideinstructions to the sub-controllers so in order to operate theapparatus.
 2. The apparatus of claim 1, wherein the base-mix modulecomprises: a base-mix holding bay suited for holding a base-mixcontainer; a pump coupled to the conduit assembly; and a source ofcompressed air coupled to the conduit assembly, the source of compressedair having an air-control valve operative to control the amount of airprovided to the conduit assembly; wherein the plurality ofsub-controllers includes a base-mix-module sub-controller coupled to thepump and operative to control the pump and the air-control valve so thatwhen base mix is loaded into the base-mix holding bay thebase-mix-module sub-controller controls the amount of base mix and theamount of air injected into the conduit assembly.
 3. The apparatus ofclaim 1, wherein the flavor module comprises: a plurality offlavor-packet holding bays operative to hold flavor packets; a pluralityof positive-displacement pumps coupled to the plurality of holding baysand operative to receive flavoring from flavor packets held in theholding bays; plurality of electrical solenoids coupled to a slidablesupport plate, each solenoid operative to engage with an associateddisplacement pump to cause the displacement pump to dispense flavoring;and a linear-drive motor, the linear drive coupled to the slidablesupport plate; wherein the plurality of sub-controllers includes aflavor-module sub-controller in communication with each of the solenoidsand with the linear-drive motor, the sub-controller being operative tocontrol each of the solenoids and the linear-drive motor so as to selectand energize a solenoid and to operate the linear-drive motor to drivethe slidable support plate moving the solenoids relative to thedisplacement pumps such that the energized solenoid causes an associateddisplacement pump to dispense flavoring.
 4. The apparatus of claim 1,further comprising a mix-ins/dried-goods module comprising: a pluralityof mix-in assemblies, each assembly comprising: a) an auger blockdefining: i) a storage container orifice configured to receive a mix-instorage container; ii) an auger passage connected to the containerorifice; and iii) a dispensing orifice connected to the auger passage;and b) an auger configured to sit in the auger passage of the augerblock, the auger having an engagable end; a plurality of driveassemblies coupled to the engagable ends of the augers and operative todrive the augers; a trough assembly having a collection slot and adispensing opening, the collection slot being coupled to the dispensingorifices of the plurality of mix-in assemblies, the trough assemblyoperative to receive mix-ins from the mix-in assemblies and to dispensethe mix-ins; wherein the plurality of sub-controllers includes amix-ins-module sub-controller in communication with each of the driveassemblies, the sub-controller operative to control the drive assembliesso that, when mix-ins containers are loaded into the mix-ins module, thesub-controller drives the engagable ends to turn the augers to dispensemix-ins.
 5. The apparatus of claim 1, further comprising a food-zoneapparatus comprising: a food-surface assembly having a flat surfacemounted for rotation about an axis; a cover positioned to substantiallyenclose at least a portion of the flat rotary surface to create a foodzone; a final mixing conduit interface coupled to the cover andconfigured to receive base mix from the base-mix module and flavoringfrom the flavor module via a final mixing conduit and to deposit the mixon the flat surface while the flat surface is rotating; a scrapercoupled to the cover and supported above the flat surface, the scraperhaving a working edge positionable to engage the rotary surface whilesaid rotary surface is rotating so as to be able to scrape the depositedmix into a ridge row on the rotary; a level coupled to the cover andspaced above the rotary surface to establish a gap, the level beingpositioned ahead of the scraper so as to be able to level the mix to aspecified height on the rotary surface while the rotary surface isrotating.
 6. The apparatus of claim 5, further comprising a rack andpinion structure coupled to the cover, the rack and pinion structurehaving a rack and pinion; a plow coupled to the rack and pinionstructure and operative to scrape the ridge row from the rotary surfaceas food product; a forming cylinder coupled to the cover and operativeto receive the food product from the plow; a diaphragm resting insidethe forming cylinder operative to form the food product into a scoop; apacking/cleaning plate rotatably coupled to the food cover via a packingplate shaft, the packing plate positioned under the forming cylinder toprovide a food product packing surface and to clean the forming cylinderbetween cleanings; a level pneumatic piston interface coupled to thelevel and operative to interface with at least one pneumatic piston toallow control of the level; a pinion pneumatic piston interface coupledto the cover and to the pinion drive and operative to interface with apneumatic piston, the piston rotated by a motor to cause rotation of thepinion; a diaphragm pneumatic piston interface coupled to the diaphragmand operative to interface with a pneumatic piston to allow control ofthe diaphragm to form the food product; a packing plate pneumatic pistoninterface coupled to packing plate shaft and operative to interface witha pneumatic piston, the piston rotated by a motor to allow positioningof the packing plate; and a plurality of features in the cover operativeto interface with pneumatic pistons to hold the cover against therotating surface.
 7. The apparatus of claim 5, further comprising aprocess box including: an electrically operated pneumatic solenoid bankhaving an air input and a plurality of air outputs; a plurality ofpneumatically driven piston assemblies, each assembly having a pistoncoupled to a pneumatic cylinder, each pneumatic cylinder coupled to anair output of the solenoid bank, the solenoid bank operative to controlair pressure in each pneumatic cylinder, each piston configured tointeract with an associated piston interface on a food zone cover; andan air compressor coupled to the air input of the solenoid bank andoperative to provide compressed air to the air input of the solenoidbank so that the solenoid bank can manage operation of the pistonassemblies to control interaction of the pistons with associated pistoninterfaces on the cover.
 8. The apparatus of claim 5, wherein thefood-surface assembly has a central axis and a periphery, and whereinthe food-surface assembly comprises: a) an upper freeze plate of whichthe flat surface is one face, the freeze plate also having a secondface, the flat surface forming a non-stick rotary freezing surface thatcan readily releases food products at low temperatures, the second facedefining a portion of a refrigerant channel operative to passrefrigerant; b) a gasket configured to couple to the second face of thefreeze plate and operative to contain the refrigerant within therefrigerant channel; c) a lower freeze plate configured to couple to theupper freeze plate and having a first face and a second face, the firstface operative to seal the refrigerant channel leaving the refrigerantchannel with an entrance orifice and an exit orifice; and d) aninsulation plate configured to couple to the lower freeze plate andoperative to provide insulation to the food-surface assembly; andwherein the apparatus further comprises: a) a drive shaft coupled to thefood-surface assembly; and b) a drive motor coupled to the drive shaftand operative to rotate the drive shaft causing rotation of the rotarysurface about the central axis; and wherein the plurality ofsub-controllers includes a sub-controller coupled to the drive motor andoperative to control the drive motor to control the rate of rotation ofthe food-surface assembly.
 9. The apparatus of claim 5, furthercomprising a refrigeration system, wherein the flat surface is a freezesurface and the food-surface assembly includes an inlet and an outletcoupled with the refrigeration system, the refrigeration systemincluding: a compressor having an inlet and an outlet, the outletproviding compressed refrigerant; a compressor discharge line attachedto the compressor outlet; a condenser having an inlet coupled to thedischarge line; a liquid-gas separator having first and second inletsand first and second outlets, the first inlet configured to receiveliquid refrigerant from the condenser, the first outlet coupled to theinlet of the compressor; a liquid stepper having an inlet and an outlet,the inlet coupled to the second outlet of the liquid-gas separator andthe outlet coupled to the inlet of the food-surface assembly; afood-surface-assembly discharge line attached to thefood-surface-assembly outlet and to the second inlet of the liquid-gasseparator; a pressure sensor coupled to the food-surface-assemblydischarge line and operative to provide a pressure signal representativeof the pressure in the food-surface-assembly discharge line; athermistor coupled to the food-surf ace-assembly discharge line andoperative to provide a temperature signal representative of thethermistor's temperature; and a hot-gas stepper valve coupled to thefood-surface-assembly discharge line and to the compressor dischargeline; wherein the plurality of sub-controllers includes arefrigeration-system sub-controller in communication with the liquidstepper, the pressure transducer, the thermistor, and the hot-gasstepper valve, the refrigeration-system sub-controller being operativeto receive a pressure signal from the pressure sensor and a temperaturesignal from the thermistor and to control at least one of the liquidstepper and the hot-gas stepper valve.
 10. The apparatus of claim 1,wherein the apparatus further includes a detector for reading aproduct-indicator label, and wherein at least one of the apparatuscontroller and the sub-controllers includes a processor coupled with acomputer-readable storage medium storing software code that providesinstructions for identifying a base mix or a flavoring based on areading of the product-indicator label and for controlling operation ofthe apparatus based on the identification.
 11. The apparatus of claim10, wherein the apparatus further comprises: a display screen, whereinat least one of the apparatus controller and the sub-controllersincludes a processor coupled with a computer-readable storage mediumstoring software code that provides instructions as to which options todisplay for available base mixes and flavorings on the display screen;and an input mechanism that a user can operate to select from theoptions that are displayed on the display screen.
 12. The apparatus ofclaim 11, wherein the computer-readable storage medium further storessoftware code that determines which options are to be displayed based onthe readings of a plurality of product-label indicators on containersfor base mixes or flavorings.
 13. The apparatus of claim 12, wherein thesoftware code includes instructions that will cause an option to beremoved from the display screen if the remaining supply of a base mix orflavoring is determined to be below a minimum threshold.
 14. Theapparatus of claim 13, further comprising a detector for detectingwhether the remaining supply of one or more base mixes or flavorings isbelow a minimum threshold.
 15. The apparatus of claim 12, wherein thesoftware code includes instructions for removing an option from thedisplay screen when a base mix or a flavoring in the apparatus fails tomeet a freshness criterion based on a reading of the product-indicatorlabel.
 16. The apparatus of claim 15, wherein the software codeinstructions for determining whether a base mix or flavoring meets thefreshness criterion based on a manufactured-on date or an expirationdate incorporated into the product-indicator label.
 17. The apparatus ofclaim 15, wherein the software code includes instructions fordetermining whether a base mix or flavoring meets the freshnesscriterion by tracking the time since the product-indicator label wasfirst detected.
 18. The apparatus of claim 12, wherein the software codeincludes instructions for recognizing when a plurality ofproduct-indicator labels refer to the same base mix or flavoring and fordisplaying a single option for that base mix or flavoring on the displayscreen.
 19. The apparatus of claim 18, where the software code includesinstructions for comparing the freshness of the base mix or flavoringassociated with each of the identical product indicator labels anddispensing from the base mix or flavoring that is nearest itsexpiration.
 20. The apparatus of claim 10, wherein the computer-readablestorage medium also stores a database including data used in formulatingprocessing instructions associated with information found in theproduct-indicator labels.
 21. The apparatus of claim 10, wherein thecomputer-readable storage medium also stores software code for haltingoperation of the apparatus upon detection of an event or absence of anevent.
 22. The apparatus of claim 21, wherein the event is unauthorizedphysical or electronic tampering with the apparatus.
 23. The apparatusof claim 22, wherein the event is removal of apparatus components forcleaning within a specified time period.
 24. The apparatus of claim 10,wherein the computer-readable storage medium also stores software codefor generating an advertisement for a product or service on the displayscreen while the apparatus is producing the food product.
 25. Theapparatus of claim 10, wherein the computer-readable storage medium alsostores software code for generating trivia relating to the food producton the display screen while the apparatus is producing the food product.26. An automated method for producing a food product, the methodcomprising: providing a vending machine in a facility, the vendingmachine including: a display screen; a base-mix module including acontainer containing base mix; a flavor module including a containercontaining flavoring; a flavor-selection assembly having an outlet and aplurality of flavoring inlets, each inlet operative to receive aflavoring, the flavor-selection assembly operative to allow passage of aflavoring from an inlet to the outlet; a food-preparation assemblyconfigured to receive the flavored, aerated mix from the distal end ofthe conduit assembly and to prepare food from the flavored aerated mix;an apparatus controller in communication with each of the plurality ofsub-controllers and operative to provide instructions to each of thesub-controllers in order to operate the apparatus; and an inputmechanism that a user can operate to select from base-mix and flavoringoptions that are displayed on the display screen; presenting selectableoptions for ice-cream ingredients on the display screen and enabling auser to operate the input mechanism to select desired options; inresponse to selected options for the base mix and flavoring from theuser, producing ice cream having ingredients corresponding to theselected options; issuing local instructions for operating the base-mixmodule, the flavor module, the flavor-selection assembly, and thefood-preparation assembly from the sub-controllers; and governing thesub-controllers using the apparatus controller.
 27. The method of claim26, further comprising automatically communicating information betweenthe vending machine and a remote controller apart from the facility inwhich the vending machine is provided.
 28. The method of claim 27,further comprising automatically detecting errors in the operation ofthe vending machine and communicating information about detected errorsto the remote controller and trouble-shooting the errors using theremote controller and sending instruction from the remote controllerback to the vending machine to a) stop production of the food productand generate a signal requesting on-site service, b) ignoring the errorand continuing production of the food product, or c) performing a repairfunction inside the vending machine and then resuming production of thefood product.
 29. The method of claim 27, further comprising generatingnew instructions for operating the vending machine to produce a new ormodified food product and downloading those instructions from the remotecontroller to the vending machine.
 30. The method of claim 26, furthercomprising testing the base-mix module, the flavor module, theflavor-selection assembly, and the food-preparation assembly using thesub-controllers before assembly inside the vending machine.